This is K.A. Subramaniya Iyer's translation of Bhartrihari's Vakyapadiya. Bhartrihari was an ancient Hindu grammarian who lived in the 5th century. But he was more than that; he was also a philosopher. Based on his study of Sanskrit grammar, he founded a philosophy of language called Sphotavada, according to which language consists of bursts of sounds called which convey meaning. This is in contrast to Varnavada, the philosophy of language most Hindus follow which says that we hear words one letter at a time and they are combined by the mind.
But Sphotavada wasn't just a philosophy of language; it also had implications for philosophy more broadly. Bhartrihari believed that sound constitutes an entity called Sabda Brahman, God in the shape of words, and that you need to realize Sabda Brahman before you can realize the supreme Brahman. Because Bhartrihari was concerned with the realization of Brahman, that makes him not just a grammarian and philosopher of language, but an early Vedantic philosopher as well. (Or at least quasi-Vedantic.) So Bhartrihari's Vakyapadiya plays an important role in the history of Hindu philosophy.
Bhartrihari also wrote a Vritti or commentary on his own Vakyapadiya. This Vritti is mostly lost, but it's at least available for chapter 1. The portion of the Vritti for chapter 1 is included in the document.
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